The Confocal Microscopy Core Facility (CMCF) is housed in the Durham Research Center (DRC), which opened in 2006. The CMCF was initiated at UNMC in 1996 and has served the research goals of >80 scientists since then. It is used extensively by scientists from the College of Medicine, the Eppley Institute for Research in Cancer and Related Diseases and the UNMC/ Eppley Cancer Center. The CMCF now maintains two confocal microscopes, a Zeiss LSM 410 and a Zeiss LSM 510 Meta. In 2006, the SIG program funded the purchase of an LSM 510 which was upgraded to an LSM 510Ma with funds provided by Vice Chancellor for Research at UNMC. The LSM 510M was put into service in early 2007, shortly after the CMCF moved to the DRC. This 10 story building, containing 136 laboratories will now become DRC I;an adjacent tower (DRC II) containing an additional 98 laboratories with added core facility space on the first floor will open in May. With few exceptions, occupancy of the lab modules is limited to current and newly recruited investigators with active research grants (NIH or equivalent) averaging >$200,000/year/module. This means that the CMCF can realistically expect an increase in the number of NIH funded investigators with need to access the CMCF for their NIH funded research. In 2006, we planned to keep both the LSM 410 and 510M in use to cover the needs of an increased number of investigators. However, only a few of our users are willing to use the limited capacity of this instrument. In contrast, the LSM 510M is in almost constant use. A technician was added to the staff so that we now have two knowledgeable people to provide assistance to investigators on weekdays from 7:30 AM to 7:30 PM (or later in special situations). Before grant dead-lines and meetings, there is often a 4-5 day wait to access the LSM 510M. Thus, it is imperative to increase our capacity. Our objective with this request for an LSM 710 is to continue providing state of the art facilities and to expand the capacity of our core to accommodate an increasing pool of NIH users. Confocal usage (hrs) in the CMCF has almost doubled since 2005 and continues to grow, making the purchase of the LSM 710 a critical need. The requested LSM 710 with Quasar spectral detection, 34 spectral detection channels and 6 laser lines- 405, 458, 488, 514, 561 and 633 nm and incubation equipment will allow the users to perform optimized co- localization of multiple fluorophores and to conveniently obtain information about protein-protein interactions and protein trafficking in live cells. The projects detailed in this proposal are selected from those of 11 major users and 23 minor users.